Humidity-controlling apparatus.



A. W. THOMPSON & E. W. COMFORT.

HUMIDITY CONTROLLING APPARATUS.

APPLICATION FILED NOV. 10. I9l5.

Patented June 5, 1917.

2 SHEETS SHEET l.

E m m lnverflors. Albert W.Thornpson Edward W.ComForT by Atty's.

A. W. THOMPSON & E. W. COMFORT. HUMIDITY CONTROLLING APPARATUS.

APPLICATION FILED NOV. 10. I915.

Patented June 5, 1917.

2 snasrs-suss1 2.

a In I E r k InvenTors. Albert W. Thompson Edward W.C0mFort b iemmaww" Mi.

Auy's.

@TATE% PATENT ALBERT W. THOMPSON, OF FITCHBURG, AND EDWARD W. COMFQRT, OF WINCHESTER,

MASSACHUSETTS, ASSIGNORS TO THE G. M.

PARKS COMPANY, OF FITGHBURG,

MASSACHUSETTS, A CORPORATION OF ll/IASSACHUSETTS.

HUMIDITY-CONTROLLIN G APPARATUS.

Specification of Letters Patent.

Patented June 5, 119117..

Application filed November 10, 1915. Serial No. 603%.

T 0 all whom it may concern:

Be it known that we, A BERT W. T OMP- SON, a citizen of the United States, and resident of Fitchburg, county of Worcester, State of Massachusetts, and EDWARD WV. COMFORT, a citizen of the United States, and resident of Winchester, county of Middlesex, State of Massachusetts, have invented an Improvement in Humidity-Controlling Apparatus, of which the followingdescription, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to improvements in thermostatic controlling devices in which suitable regulating means are controlled by the conjoint action of two expansible members subjected to different temperature conditions.

More specifically the invention comprises improvements in humidifier regulators which are controlled by the differential expansion of two members exposed respectively to the wet and dry bulb temperatures of the atmosphere.

The principal object of the invention is to produce a simple, accurate, and reliable apparatus of this class which will have a minimum number of parts, which may be readily adjusted to respond to any desired hygrometric condition of the atmosphere and which may easily be cleaned, so that the accuracy of the instrument may not be impaired.

Apparatus hitherto used in the effort to maintain the wet bulb member at the psychrometnic or hygrometric wet bulb temperature of the atmosphere and at the same time to secure conditions which will make the same sensitive to changes in temperature conditions may be divided into two classes:

1st, hygrometric instruments,in which the wet bulb member is covered by a mantle depending upon capillary action to conduct water from a reservoir to the surface of the wet bulb member and,

2nd, psychrometric instruments,-in which the wet bulb memberis exposed to a sample of saturated air, from some type of hue midifier, or is directly exposed to a jet of spray and air, or is maintained moist and exposed to a continuous blast of air traveling at a sufficiently high velocity to cause the necessary rate of evaporation to maintain the temperature of the member at the psychromet-ric, wet bulb temperature.

Instruments of the first class are rendered unreliable because of the fact that the mantle rapidly becomes clogged with material precipitated from the solution by evaporation of the water and with deposits of impurities from the air to which it is necessarily exposed, thus requiring frequent cleansing or replacement of the mantle to maintain the instrument in proper c0ndition.

Instruments of the second class as heretofore constructed have involved the use of extremely delicate and special mercurial thermometers and of highly sensitive electrical apparatus or complex mechanical sys toms of transmission, and as the air used in all such instruments can only be cleaned to a limited extent by passing through a screen of sufficiently coarse mesh to avoid excessive resistance the instrument is frequently glogged and rendered inaccurate by lint and irt.

One feature of the present invention comprises the avoidance of these defects by maintaining the surface of the wet bulb member in a continuously moist condition by a supply of water derived by precipitation from a supersaturated sample of the air of the inclosure, the condition of which is subject to regulation. said water being filtered and delivered to the wet bulb member at its psychrometric wet bulb temperature. The wet bulb ,member may convenientlv be maintained at said psychrometric wet bulb temperature by evaporation caused by passing the sample of air over its moistened surface preferably by the inspiration peratures corresponding to this condition. In case of saturation of the atmosphere these temperatures are alike and the ratio is .1. For any other condition the dry bulb temperature is higher and for the ordinary temperatures is a constant multiple of the wet bulb temperature for that condition, provided a point about four degrees F. above zero is taken as the point from which to reckon.

As the dry bulb temperature is greater and is subject to greater temperature changes than the wet bulb temperature for all. conditions except saturation it follows that if in regulating apparatus of this kind a condition of saturation is to be maintained the expansible elements must be of equal length to maintain equal action upon the controlling mechanism.

If any other condition of humidity obtains the wet bulb member must be longer than the dry bulb member, owing to the less range of temperature to which it is exposed, and the relation of the length of the Wet bulb member to the length of the dry bulb member will be identical with the relation formula 335%; in which in; represents the wet bulb temperature and ti the dry bulb temperature. In order that the apparatus may be set for any desired humidity condition it is therefore desirable that means he provided for adjusting the effective lengths of the wet and dry bulb members to the ratio required for the condition to which the humidity of the atmosphere is to be regulated. This is accomplished in the preferred embodiment of the invention disclosed herein by providing wet and dry bulb members preferably having the same coeflicient of expansion and by equipping one of said members with means whereby its efiective expansible length may be varied to suit the conditions of temperature and relative humidity of the inclosure or room under treatment without changing the co-efiicient of expansion of said member.

Other objects of the invention will more fully appear from the following description and the accompanying drawings and will be pointed out in the annexed claims.

The drawings illustrate a preferred form of regulating device adapted to control the operation of a compressed air system not shown which may be used to regulate the heat supplied to a room or the amount of moisture delivered thereto or to effect any other function which may be desirable.

It will be understood however that our invention is equally adapted to control electric circuits or other means which in turn may serve to control regulating apparatus of the character above mentioned.

In the drawings,

Figure l is an elevation partly in section of a thermostatic regulator embodying one of the preferred forms of our invention, the door being broken away to disclose the mechanism contained in a suitable casing, portions of the mechanism therein being shown in section.

Fig. 2 is a transverse sectional view on lines 22 Fig. 1 looking downwardly.

Fig. 3 is a detail view of the mechanism for regulating the elfective length of the dry bulb expansible member.

Fig. 4t is a detail longitudinal sectional view of the conduit leading tothe regulating valves showing particularly the form of the restricting valve in the conduit which is controlled by the conjoint action of the expansible members.

Fig. 5 is a vertical sectional view of the regulating valve which controls the mechanism for maintaining the atmosphere of the inclosure at the desired condition of relative humidity.

The preferred embodiment of the invention comprises a closed rectangular casing having a base 1 and a preferably pivotally mounted door 2 provided with a glass panel to permit inspection of the indicating device inclosed within the casing. The casing preferably is divided into three compartments 3, e and 5 separated by partitions 6, 7 and 8 which extend from the ends of the casing and which are provided respectively with apertures 9, 10 and 11 adapted to permit the passage of the air from each chamher to the next, the air being introduced through a conduit 12 in the base of the chamber 5 and permitted to pass out through an opening in the top of the chamber 3 leading to an auxiliary conduit or chamber 13.

The thermostatic regulating device comprises a preferably hollow cylindrical wet bulb member 14 of ebonite or other suitable material which may be screw threaded at its bottom and seated in a base 15 secured to a bracket 16 within the casing and a preferably cylindrical dry bulb member 17 of like material similarly seated in a base 18 secured to the bracket 19 which conveniently may be a horizontal offset portion of the partition between the chambers 4 and 5. In order to utilize the difi'erential expansion of the wet and dry bulb members the upper portion of each member is provided with a head which is connected to a lever 20 adapted to regulate a valve controlling a by-pass leading from a regulating valve preferably of the diaphragm type and which is adapted to control the operation of said valve.

In the preferred embodiment of the invention illustrated herein the lever 20 is aser/is preferably constructed of metal and is in the form of an inverted 'l', the arms 21 and 22 of which are connected by leaf springs 23, 24 to the lower ends of rods 25, 26 preferably of invar steel, which has practically no co-efiicient of expansion, extended axially upwardly through the wet and dry bulb members respectively and which are connected at their upper ends to heads 27, 28 which are provided with screw threaded peripheries engaging corresponding screw threads in the inner walls of the wet and dry bulb members so that there is always a rigid connection between the otherwise free ends of the wet and dry bulb members and the ends of the arms 21, 22 of the l -shaped 'lever 20. Any suitable means may be provided to permit vertical movement of the lever 20 when the Wet and dry bulb members expand together or contract together without displacing said lever laterally. In the particular mechanism disclosed herein the lower end of the lever 20 is provided with a downward projection 20 which is pivotally connected to a link 2O which in turn is pivoted upon'a stud 20 extending from the back of the casing. It will be obvious that this connection will maintain the lever 20 in proper relation to the wet and dry bulb member and to the lever 31 which controlsthe outlet of the conduit 25 so that the operation of the device will be insured under all conditions of operation. The lever 20 is preferably provided at its opposite end with a screw 29 having a sharp conical end 30 which bears upon the lower end of a lever 31 which is mounted upon a knife edge 32 and at its opposite end is provided with a flat surface 33 serving as a valveto close the port in a nipple 3a which communicates with a tube or conduit 35 leading to the relay valve above mentioned and which will hereinafter be described.

A helical spring 36 connected to the lever 31 and to a stationary member 37, which may provide a continuation of the conduit 35, serves to retain the lever 31 in place.

Inasmuch as it is desirable to vary the effective length of the dry bulb member only, the head 27 is securely and permanently seated in the upper endof the wet bulb member. The head 28 in the dry bulb member however is so constructed as to be adjustable to vary the efi'ective length of the dry bulb member. In the preferred embodiment of the invention illustrated herein this is accomplished by providing screw threads upon the rod 26 of the same pitch as the screw threads upon the inner surface of the dry bulb member 17 and providing means for rotating said head whereby the same may be located at any desired position along the interior wall of the dry bulb member. A convenient means for accomplishing this purpose is illustrated herein which cont prises a spanner consisting of a member 38 rotatably mounted in a bracket 39 having a stem 40 extending through the casing and secured thereby to a nut 41. Said member 38 is provided with a knurled adjusting knob 42 resting upon the upper portion of the bracket and at its bottom provided with rods 43, 44: extending respectively through suitable apertures 45, 46 in the head 28.

It will be obvious that by rotating the adjusting knob/l2 the head 28 will be rotated within the dry bulb expansion member 17 and by reason of its screw threaded connec tion therewith and with the rod 26 will be adjusted up and down to vary the efiective length of said member. it will also be apparent that when the head 23 is adjusted up or down the length of the rod 26 will be increased or diminished exactly the same amount as the elfective length of the expansion member is increased or diminished so that the co-eflicient of expansion of said member plus the co-efiicient of expansion of the rod 26 which connects it to the lever 20 will remain constant throughout the entire range of adjustment of the efiective length of the expansible member. By reason of this construction the inverse ratio of the actual eflective length of the expansible members for any desired condition of hu midity corresponds to the ratio, or the relation between the dry bulb temperature and the wet bulb temperature at said constant of humidity.

In order conveniently to indicate the proper adjustment, the dry bulb member is provided with a longitudinal slot 47 which will expose the edge of the head, and a scale ebonite covered with a mantle 49 of filter paper, muslin or other suitable material, said mantle preferably extending slightly above the end of the dry bulb member to receive and distribute the water supplied to it.

The surface of the wet bulb member in our preferred embodiment of the invention is supplied with water delivered to it preferably at the psychrometric wet bulb temperature of the atmosphere in the following manner: The upper end of the wet bulb member is disposed at a distance from the upper end ofthe casing and vaporizing means, preferably in the form of a turbo head of the character described in the patent to Albert W. Thompson, No. 869,945, granted November 5, 1907 is introduced 1n substantially axial alinement with the wet bulb member. The turbo head is carried by a bracket 51 detachably fastened to the side of the casing, water-being introduced into said turbo head through a conduit 52 and compressed air supplied thereto through the conduit 53.

In operation the turbo head discharges a finely divided spray 54 into the auxiliary chamber 13 which communicates with the upper end of the main casing. This auxiliary chamber preferably is in the form of a cylinder 55 of glass or other suitable smooth material which is provided at its bottom with a collar 56 adapted to rest upon the outer side of the casing. The lower end of the cylinder 55 preferably telescopes within the upper end of a trough shaped member 57 secured to and depending within the casing. An annular disk of filter paper 58 or other absorbent material is preferably clamped between the lower end 56 of the cylinder 55 and the trough and serves to remove the impurities from the water which is precipitated upon the wall 55 of the cylindrical chamber 13. a

Any other suitable filtering mechanism may be provided, the essential feature being that the filtering medium may be readily accessible so that it may be removed and replaced without inconvenience.

The precipitated fluid may conveniently be conducted from the trough to the wet bulb member by a tube or rod 59 communicating with the interior of the trough and resting at its lower end upon the extended end of the mantle 4:9. It will be readily understood that in the operation of the device any desirable amount of water may be atomized and forced through the auxiliary chamber 13 so that the sample of atmosphere passing therethrough will be supersaturated to any desired extent, consequently the amount of water delivered to the wet bulb member may be regulated to insure the delivery of a suflicient quantity of water to envelop the surface of the wet bulb member throughout its entire length and thus maintain the wet bulb member constantly at the Wet bulb temperature of the atmosphere.

Excess of water may be discharged through a conduit leading from the lower end of the wet bulb chamber. Ordinarily the drainage of water from the auxiliary chamber will be. at the psychrometric wet bulb temperature of the atmosphere. If, however, the discharge from the vaporizer is excessive so that the water delivered to the wet bulb expansion member is not reduced to the psychrometric wet bulb temperature the evaporation caused by the current of air,:

meagre induced by the vaporizer through the wet bulb chamber, passing over the wet bulb member will serve to maintain the wet bulb member at the psychrometric wet bulb temperature of the atmosphere, thus insuring ac curacy in operation of the instrument.

In order to aid the operator in adjusting the apparatus and to enable him to determine whether the same is working properly a thermometer conveniently may be supported on the door of the casing, having its stem offset to extend through the casing so that the bulb 61 will lie adjacent to the wet bulb expansion member. By placinga covering 62 of cotton or other absorbent material upon the bulb of the thermometer so that it rests against the mantle, the thermometer will be supplied with fluid at the same temperature as that which influences the wet bulb member; furthermore this thermometer, lying in the path of the current of air induced by the vaporizer, will be maintained at absolutely the same temperature as that which affects the wet bulb expansion member. For comparison of the wet and dry bulb temperatures a dry bulb thermometer 63 may conveniently be located upon the door of the casing adjacent to the thermometer 60, thus enabling the operator to determine when the controller is working properly, or if automatic regulation is not desired to merely indicate the dry and wet bulb temperatures of the atmosphere.

While the regulating apparatus thus de-' scribed is adapted to control any system either mechanical or electrical for regulat-- ing the amount of moisture supplied to a room or the amount of heat supplied thereto or to efl'ect any other function usually accomplished by regulators we have illustrated this thermostatic regulating device as applied to a relay valve for controlling a pneumatic system of regulation, the source of energy being preferably compressed air, or like fluid.

In the preferred form ,of construction illustrated herein the relay valve together with a pressure gage and an instrument for indicating Whether the source of energy is turned on or off are inclosed within the chamber 5 of the casing, the dials of the indicator and gage being located behind the glass panel 3 of the door.

The relay valve may be of any suitable character but preferably is in the form of a diaphragm valve operated from a source of compressed air and controlled by the opening and closing of the valve of the Toy-pass 35 by the conjoint action of the wet and dry expansible members in the manner heretofore described.

The relay valve comprises a cup shaped receptacle 65 the base or which may be provided with a stud 66 adapted to extend through the base 1 of the casing and to be 5 said receptacle. The compressed air pipe 63, may also communicate with the branch pipe or conduit 35.

The top of the receptacle 65 is covered by a diaphragm which supports centrally a valve head 71 which is adapted to open and close a port 71 in a compressed air conduit leading to a suitable regulating valve of the system to be controlled.

As illustrated herein the compressed air conduit which supplies air to the relay valve and also to the regulating valve comprises an inlet pipe 72 leading through the side or bottom of the casing, preferably to a chamber 73 in a cylindrical member 74 which may be suitably secured within said casing, the chamber 73 being rendered accessible by a screw threaded cover 75 fitting in the end of, the member 74. The chamber 73 may be filled with filtering material 76 such as gauze adapted to remove the impurities from the air. The filtered compressed air leaving the chamber 73 is led through two passages one of which communicates through the relay valve with the main regulating valve of the system and the other of which leads to the chamber beneath the diaphragm 70.

In order to provide for a sensitive regulation of the relay valve the flow of compressed air which is introduced beneath the diaphragm 70 is restricted. This may be accomplished by a restricting valve of the type illustrated in Fig. 4.- in which the compressed air passes from the conduit 77 through a restricted opening 78 which may conveniently be provided by forming a nipple 79 upon the member 7 4 at right angles to the axis thereof, th nipple being apertured to receive a pin 80 extending into the end of the conduit 69 leading to the chamber of the receptacle 65 below the, diaphragm valve, the side of the pin 80 being slabbed ofl" to provide the restricted passage 78. The nipple may be covered by a screw threaded cap 81 adapted to be removed so that the pin 80 may be withdrawn for purposes of cleaning or for adjustment.

By reason of the restricted amount of compressed air supplied beneath the diaphragm 70 the opening and closing of the aperture in the by-pass 35 will quickly effect the operation of the valve 71.

The compressed air is also led from the chamber 73 through a conduit 82 to the relay valve. As illustrated herein this comprises a tube leading to an aperture 83 in the wall of the receptacle 65 thence through a yoke 84 extending above and diametrically across the diaphragm. p i

This yoke is provided centrally with a downwardly extending boss 85 which is centrally apertured to receive the hollow stem 86 of a valve 87 adapted to control the passage of compressed air to the main regulatlng valve.

The boss 85 may be provided with a gland 88 in which the packing is retained by a screw threaded cap 89. The stem 86 of the valve 87 passes through an aperture 90 in the yoke considerably larger than the diaphragm of the stem, the head of the valve however being of sufiicient size to close said aperture and being maintained normally seated upon the mouth of said aperture by a spring 91 which may conveniently be retained in place by a cap 92 secured upon a hollow boss 93 extending upwardly from the yoke 84 and providing an air chamber with which the conduit 83 communicates. A conduit 94 leads from the aperture 90 through the opposite arm of the yoke to the main regulating valve, not shown.

In operation the main regulating valve is ordinarily retained in closed position by the supply of compressed air through the conduit 95 leading from the relay valve thereto. \Vhen the atmosphere is at the predetermined condition of humidity the port of the by-pass 35 is closed by the valve 33 of the lever 31. \Vhen, however, the relative humidity falls below the predetermined point the lowering of the temperature of the wet bulb member or the raising of the temperature of the dry bulb member or the conjoint action of both will actuate the lever 20 to open the port of the conduit 35 thus relieving the pressure beneath the diaphragm 70 of the regulating valve. This causes the withdrawal of the valve 71 from the port 71 in the stem 86 of the valve 87, releasing the pressure upon the main regulating valve and operating it to turn on the humidifying system or to accomplish such other purpose as may be provided for. At the same time the spring 91 forces the valve 87 into contact with the port of the passage 90, thus closing off the supply of compressed air from the conduit 94, 95 leading to the main regulating valve. Conversely, when the predetermined condition of humidity again is attained by the additional moisture thus supplied the changes in the temperature of the wet and dry bulb members will by the reversed action of either or both operate to close the valve of the conduit 35 so that the diaphragm 70 will be raised by the accumuduit 94 to the main regulating valve thus providing for the shutting oif of the supply of moisture.

It is to be understood that the particular embodiment of the invention disclosed herein is illustrative and not restrictive and that the principles of the invention may be ap plied in other forms of apparatus Within the terms of the following claims.

While the apparatus has been herein described as applicable to the regulation of a humidifying system it will be obvious that it is adapted forthe regulation of any source of energy Which it may be desirable to control in conformity to the relative humidity of the atmosphere.

plying the wet bulb member With moisture precipitated from a supersaturated sample of atmosphere and collected by means other than the walls of said wet bulb member.

2. In a thermostatic regulating device comprising expansible membersadapted for exposure respectively to the dry and wet bulb temperatures of the atmosphere and means operable by their conjoint action to control a source of energy; means for supplying the Wet bulb member with an en-- velop of moisture precipitated from a supersaturated sample of atmosphere collected by means other than the Walls of said wet bulb member, and means for maintaining the envelop of moisture at the Wet bulb temperature of the atmosphere.

3. In a thermostatic regulating device comprising expansible members adapted for exposure respectively to the dry and wet bulb temperatures of the atmosphere, and means operable by their conjoint action to control a source of energy; means for causing a sample of atmosphere to traverse successively the dry and wet bulb members, means for super-saturating said sample of atmosphere thereafter, means for precipitating and collecting excess moisture therefrom and means for enveloping said Wet bulb member in the precipitated fluid thus obtained.

4. In a thermostatic regulating device comprising expansible members adapted for exposure respectively to the dry and wet bulb temperatures of the atmosphere with means'operable by their conjoint action to control a source of energy; means for causing a continuous sample of atmosphere to traverse successively the dry and Wet bulb members, means for continuously supersaturating said sample of atmosphere thereafter, means for filtering and collecting ex: cess moisture precipitated therefrom and 'means for surrounding said Wet bulb member by an envelop of the precipitated fluid thus obtained.

5. A thermostatic regulator comprising a casing having a plurality of chambers accessible to the atmosphere of a room; dry and wetbulb expansible members in said chambers each having one end immovably fixed within said casing, means adapted to control a source of energy connected to said dry and Wet bulb members at suitable distances from their fixed ends, an auxiliary .chamber, means for supersaturating a sample of air from said room in said auxiliary chamber, means for collecting moisture precipitated therefrom in said auxiliary cham her and means for supplying the precipitated fluid to the wet bulb member.

6. A humidity indicator comprising dry and wet bulb thermometers, means for causing a continuous sample of atmosphere to traverse successively the bulbs of said dry and wet bulb'thermometers, means for continuously'supersaturating said sample of atphere, an auxiliary chamber communicating with the wet bulb thermometer inclosing 5 chamber means for inducing a continuous sample of the atmosphere of the room successively through the dry and Wet bulb thermometer inclosing chambers and for supersaturating said sample of atmosphere in the auxiliary chamber, means for collecting excess moisture precipitated in said auxiliary chamber and means for supplying the bulb of the wet bulb member with the precipitated fluid thus obtained.

8 A thermostatic regulator comprising a casing having a plurality of chambers accessible to the atmosphere of a room, dry and wet bulb expansible members in said chambers each having one end immovably fixed Within said casing, a thermometer having its bulb in the wet bulb chamber, means adapted tocontrol a source of energy connected to said dry and wet bulb members at suitable distances from their fixed ends, an auxiliary chamber, means for super-saturat- .ing a sample of air from said room in said auxiliary chamber, means for collecting moisture preclpltated therefrom in said auxiliary chamber and means for supplying the precipitated fluid to the wet bulb member and to the bulb of the thermometer located Within the wet bulb chamber, and athermometer subject only to the action of the room temperature in proximity to said wet bulb thermometer, whereby the dry and wet bulb temperature of said atmosphere may readily be observed.

9. A thermostatic regulator comprising a casing having a plurality of chambers accessible to the atmosphere of a room, dry and wet bulb expansible members in said chambers each having one end immovably fixed within said casing, means adapted to control a source of energy connected to said dry and wet bulb members at suitable distances from their fixed ends, a conduit deiilachably connected to said casing forming an auxiliary chamber communicating with said wet bulb chamber, means for inducing a sample of atmosphere from the room through said Wet bulb chamber and supersaturating the same in said auxiliary chamber, means for collecting moisture precipitatcd in said auxiliary chamber and means for supplying the same to the wet bulb mein er.

10. A thermostatic regulator comprising a casing having a plurality of chambers accessible to the atmosphere of a room, dry and wet bulb expansible members in said chambers, each having one end immovably fixedwithin said casing, means adapted to control a source of energy connected to said dry and wet bulb members at suitable distances from their fixed ends, a conduit de tachably connected to said casing forming an auxiliary chamber communicating with said Wet bulb chamber, filtering means removably secured adjacent the base of said conduit, means for inducing a sample of at mosphere from the room through said wet bulb chamber and for super-saturating the same in said auxiliary chamber, means for collecting the filtered precipitated moisture draining from said auxiliary chamber and means for supplying the same to the wet bulb member.

11. A thermostatic regulator comprising a casing having a plurality of chambers accessible to the atmosphere oi a room, dry and ti d wet bulb expansible members in said chambers each having one end immovably fixed within said casing, a lever having arms connected respectively to said dry and wet bulb members -at suitable distances from their fixed ends and means for controlling a source of energy, means for causing a sample of atmosphere to pass through'the wet bulb chamber and for super-saturating the same thereafter, means for collecting moisture precipitated therefrom and means for supplying the precipitated fluid to the wet bulb member.

12. A thermostatic regulator comprising a casing having a plurality of chambers accessible' to the atmosphere of a room, dry and wet bulb expansible members in saidchambers each having one end immovably fixed within said casing; means adapted to control a source of energy connected to said dry and wet bulb members at suitable distances from their fixed ends, an auxiliary chamber communicating with said wet bulb chamber, an atomizer adapted to supply spray continuously to super-saturate the atmosphere in said auxiliary chamber and by inspiration to induce a current of air through said wet bulb chamber, means for collecting moisture precipitated in said auxiliary chamber and means for surrounding said wet bulb member with an envelop of the precipitated fluid whereby said wet bulb member will be maintained at the wet bulb temperature of the atmosphere of the room.

13. A thermostatic regulator comprising a casing having a plurality of communicaing chambers, dry and wet bulb expansible members in said chambers each having one end immovably fixed within said casing, a lever-having divergent arms connected respectively to said dry and wet bulb members at suitable distances from their fixed ends and an arm operatively connected to a device for controlling a source of energy; means for causing a continuous sample of the atmosphere of an mclosure to pass suc- ,cessively through the dry and wet bulb chambers, and for super-saturating the same thereafter in an auxiliary chamber, and means for supplying the precipitated-fluid to the wet bulb member.

14. A thermostatic regulating device comprisin wet and dry bulb expansible members o difi'erent predetermined lengths, each having a-uniform coefficient of expansion independent of its length, the ratio of the length of the wet bulb member to the length of the dry bulb member being identical with the relation between the dry bulb temperature and the wet bulb temperature at a desired condition of humidity.

15. A thermostatic regulating device comprising wet and dry bulb expansible members of different predetermined lengths both having the same uniform co-efficient of expansion independent of their lengths, the ratio of the length of the wet bulb member to the dry bulb member being identical with the relation of the dry bulb temperature to the wet bulb temperature at a desired condition of humidity.

16. A thermostatic regulating device comprising wet and dry bulb expansible members of relatively adjustable lengths, each member having a constant co-efiiment of ex pansion throughout the adjustment thereof, the ratio of the len th of the wet bulb member to that of the dry bulb member for any 17. A thermostatic regulating device comprisin wet and dry bulb expansible members o relatively adjustable lengths, means for adjusting the effective length of the dry bulb member to a predetermined relation to the length of the wet bulb member, each member having a.constant co-efiicient of expansion throughout its adjustment and means operable by their conjoint action to control a source of energy.

18. A thermostatic regulating device c0mprising wet and dry bulb expansible members of relatively adjustable lengths, means for adjusting the effective length of the dry bulb member to a predetermined relation to the length of the wet bulb member, each member having a constant co-eiiicient of expansion throughout its adjustment and means operable by their conjoint action to control a source of energy, in combination with a scale the graduations of which correspond the Wet bulb member to the dry bulb member under different conditions of humidity.

19. In a thermostatic regulating device comprisingexpansible members adapted for exposure respectively to the dry and wet bulb temperatures of the atmosphere, means for maintaining the wet bulb member at the psychrometric wet bulb temperature of the atmosphere, means for adjusting and for correlating the effective length of the dry bulb member in a predetermined ratio to the length of the wet bulb member corresponding inversely to the relation of the dry bulb temperature to the wet bulb temperature of the atmosphere at a predetermined condition of humidity.

20. A thermostatic regulator comprising expansible elements adapted for exposure to the dry and wet bulb temperatures of the atmosphere with means operable by the conjoint action of said members to control. a source of energy, means for adjusting relatively the effective lengths of said dry and wet bulb members and for correlating the effective lengths of the same to correspond inversely to the relation of the dry to the wet bulb temperature of the atmosphere at a predetermined condition of humidity, means for causing a continuous sample of the atmosphere to traverse successively the 'dry and wet bulb members, means for supersaturatingthe sample of atmosphere thereafter, means for precipitating and collecting excess moisture therefrom, and means for enveloping said wet bulb member in the precipitated fluid thus obtained.

21. A thermostatic regulator comprising a pneumatically actuated relay valve adapted to control a source of energy, a bypass for to the inverse ratio of the length of means controlling said relay valve, a valve for said by-pass, expansible members adapted for exposure to the dry and wet bulb temperaturesof the atmosphere, means operable by the conjoint action of said members to control the bypass valve, means for causing a continuous sample of the atmosphere to traverse successively the dry and wet bulb members, means for supersaturating the sample of atmosphere thereafter, means for precipitating and collecting excess moisture therefrom, and means for enveloping said wet bulb member in the precipitated fluid thus obtained.

22. A thermostatic regulator comprising a pneumatically actuated relay valve adapted to control a source of energy, a bypass for controlling said relay valve, a valve for said bv-pass, expansible members adapted for exposure to the dry and wet bulb temperatures of the atmosphere, means for adjusting relatively the effective lengths of said dry and wet bulb members to conform to the ratio of the dry and wet bulb temperatures of the atmosphere at a predetermined condition of humidity, means operable by the conjoint action of said members to control the by-pass valve, means for causing a continuous sample of the atmosphere to traverse successively the dry and wet bulb members, means for supersaturating the sample of atmosphere thereafter, means for precipitating and collecting excess moisture therefrom, and means for enveloping said wet bulb member in the precipitated fiuid thus obtained.

23. In a thermostatic regulating device,

hollow cylindrical expansion members adapted for exposurerespectively to the dry and wet bulb temperatures of the atmosphere, means for immovably retaining one end of each member, means for supplying the wet bulb member with an envelop of moisture, means, operable by the conjoint action of said members to control a source of energy, fixedly secured to said wet bulb member at a suitable distance from its fixed end and adjustably secured to the dry bulb member at a distance from its fixed end.

24. In a thermostatic regulating device, hollow cylindrical expansion members adapted for exposure respectively to the dry and wet bulb temperatures of the atmosphere,

means for immovably retaining one end of each member, a lever, operable by the conjoint action of said expansible members to control a source of energy, fixedly secured to a head in said wet bulb member at a suited for exposure respectively to the dry and threaded connections with the interior wall Wet bulb temperatures of the atmosphere, of said dry bulb member, a screw threaded means for immovably retaining one end of rod engaging axially said head connected each member, means for supplying the wet to said lever and spanner for rotating said 5 bulb member with an envelop of moisture, head. 15 a lever, operable by the conjoint action of In testimony whereof, we have signed our said expansible members to control a source names to this specification. of energy, fixedly secured to a head in said wet bulb member at a suitable distance from ALBERT W. THOMPSON.

10 its immovable end, a head having screw EDWARD W. COMFORT. 

